Ensuring the demographic and genetic viability of small populations of threatened primates requires a range of management approaches. Here we describe a novel mixed in situ and ex situ management project that was developed to restore a population of the Critically Endangered northern muriqui Brachyteles hypoxanthus. This isolated population, located in Ibitipoca, Lima Duarte, Minas Gerais, Brazil, had declined to two adult males and would have gone extinct without intervention. A first attempt at in situ management in 2017 involved the translocation of a solitary female from another region, but this female did not associate or interact with the males and disappeared after 9 months. We thus initiated a second and ongoing ex situ management project that involved constructing a complex consisting of a large, open-air enclosure abutting a small patch of forest surrounded by an open area in the process of restoration, all of which is protected by electric fencing. The entire area within the fencing is called Muriqui House. The two Ibitipoca males and two solitary, wild females from another location were captured and released into the enclosed part of Muriqui House between March 2019 and January 2020 and into the forested part of Muriqui House in February 2020. The birth of an infant in this group in November 2020 and the acceptance by the group of a third female translocated from another area in January 2021 demonstrate the potential of this approach for the recovery of this isolated population, with positive implications for the conservation of the species.

Social camouflaging (SC) is a set of behaviors used by autistic people to assimilate with their social environment. Using SC behaviours may put autistic people at risk for poor mental health outcomes. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the goal of this systematic review was to investigate the development of SC and inform theory in this area by outlining the predictors, phenotype, and consequences of SC. This review fills a gap in existing literature by integrating quantitative and qualitative methodologies, including all gender identities/age groups of autistic individuals, incorporating a large scope of associated factors with SC, and expanding on theory/implications. Papers were sourced using Medline, PsycInfo, and ERIC. Results indicate that self-protection and desire for social connection motivate SC. Camouflaging behaviors include compensation, masking, and assimilation. Female individuals were found to be more likely to SC. Additionally, this review yielded novel insights including contextual factors of SC, interpersonal relational and identity-related consequences of SC, and possible bidirectional associations between SC and mental health, cognition, and age of diagnosis. Autistic youth and adults have similar SC motivations, outward expression of SC behavior, and experience similar consequences post-camouflaging. Further empirical exploration is needed to investigate the directionality between predictors and consequences of SC, and possible mitigating factors such as social stigma and gender identity.

While humans are highly cooperative, they can also behave spitefully. Yet spite remains understudied. Spite can be normatively driven and while previous experiments have found some evidence that cooperation and punishment may spread via social learning, no experiments have considered the social transmission of spiteful behaviour. Here we present an online experiment where, following an opportunity to earn wealth, we asked participants to choose an action towards an anonymous partner across a full spectrum of social behaviour, from spite to altruism. In accordance with cultural evolutionary theory, participants were presented with social information that varied in source and content. Across six conditions, we informed participants that either the majority or the highest earner had chosen to behave spitefully, neutrally or altruistically. We found an overall tendency towards altruism, but at lower levels among those exposed to spite compared with altruism. We found no difference between social information that came from the majority or the highest earner. Exploratory analysis revealed that participants’ earnings negatively correlated with altruistic behaviour. Our results contrast with previous literature that report high rates of spite in experimental samples and a greater propensity for individuals to copy successful individuals over the majority.

Childhood maltreatment (CM) has been related to social functioning and social cognition impairment in people with psychotic disorders (PD); however, evidence across different CM subtypes and social domains remains less clear. We conducted a systematic review and meta-analysis to quantify associations between CM, overall and its different subtypes (physical/emotional/sexual abuse, physical/emotional neglect), and domains of social functioning and social cognition in adults with PD. We also examined moderators and mediators of these associations. A PRISMA-compliant systematic search was performed on 24 November 2022 (PROSPERO CRD42020175244). Fifty-three studies (N = 13 635 individuals with PD) were included in qualitative synthesis, of which 51 studies (N = 13 260) with 125 effects sizes were pooled in meta-analyses. We found that CM was negatively associated with global social functioning and interpersonal relations, and positively associated with aggressive behaviour, but unrelated to independent living or occupational functioning. There was no meta-analytic evidence of associations between CM and social cognition. Meta-regression analyses did not identify any consistent moderation pattern. Narrative synthesis identified sex and timing of CM as potential moderators, and depressive symptoms and maladaptive personality traits as possible mediators between CM and social outcomes. Associations were of small magnitude and limited number of studies assessing CM subtypes and social cognition are available. Nevertheless, adults with PD are at risk of social functioning problems after CM exposure, an effect observed across multiple CM subtypes, social domains, diagnoses and illness stages. Maltreated adults with PD may thus benefit from trauma-related and psychosocial interventions targeting social relationships and functioning.

For infections to be maintained in a population, pathogens must compete to colonize hosts and transmit between them. We use an experimental approach to investigate within-and-between host dynamics using the pathogen Pseudomonas aeruginosa and the animal host Caenorhabditis elegans. Within-host interactions can involve the production of goods that are beneficial to all pathogens in the local environment but susceptible to exploitation by non-producers. We exposed the nematode host to ‘producer’ and two ‘non-producer’ bacterial strains (specifically for siderophore production and quorum sensing), in single infections and coinfections, to investigate within-host colonization. Subsequently, we introduced infected nematodes to pathogen-naive populations to allow natural transmission between hosts. We find that producer pathogens are consistently better at colonizing hosts and transmitting between them than non-producers during coinfection and single infection. Non-producers were poor at colonizing hosts and between-host transmission, even when coinfecting with producers. Understanding pathogen dynamics across these multiple levels will ultimately help us predict and control the spread of infections, as well as contribute to explanations for the persistence of cooperative genotypes in natural populations.

While the use of salivary cortisol as an index of hypothalamic–pituitary–adrenal (HPA) axis activation has increased rapidly in human studies, few non-human primate studies have used saliva samples. Nearly 300 h of behavioural data and over 400 saliva samples were collected from three young adult, male western lowland gorillas to document the feasibility and effectiveness of using salivary cortisol as an index of HPA activation in gorillas. Cortisol concentrations were significantly higher in morning samples than in afternoon samples, and there was a significant decrease in morning cortisol concentrations across the study period. Additionally, acute increases, followed by a return to baseline concentrations of cortisol were observed. Salivary cortisol concentration was found to correlate across individuals, indicating potential psychological attunement to environmental and/or social variables in these animals. Although no clear relationship between behaviour and cortisol concentrations was established, these results indicate that salivary cortisol is an effective technique for documenting HPA activity over an extended period of time, as it allows for detection of diurnal variation as well as acute changes in salivary cortisol concentrations.

Some aspects of on-farm assessment of social behaviour and avoidance distance were investigated on 20 Austrian dairy farms. The avoidance distance of at least 75% of cows was assessed. Social behaviour of the cows was observed for one hour and the number of animals standing was recorded every 10 min. Lameness of each animal was scored, and Spearman correlations were calculated. Generally, the avoidance distance of the cows was very low. Lameness did not correlate significantly with avoidance distance. The number of agonistic interactions with body contact per cow correlated negatively with the percentage of lame animals (rs = -0.49; P = 0.029). However, this correlation was no longer found (rs = -0.22; not significant) when calculated on the basis of standing animals only. The total number of social interactions correlated highly with the number of social interactions when interactions in the feeding rack were disregarded. The present study suggests that lameness confounds the assessment of social behaviour but not that of avoidance distance of cows, and that social interactions of animals standing in the feeding racks can be disregarded without decreasing the reliability of the assessments.

Efforts to promote the psychological well-being of captive non-human primates through the application of environmental enrichment techniques are becoming more common. However, from this perspective relatively little empirical work has been done on the effects of manipulation of the social environment. The data currently available indicate that primates kept in solitary confinement are likely to develop a variety of behavioural and physiological disturbances reflecting reduced well-being, whereas most compatibly socially housed primates appear better adapted. There is always some risk associated with manipulating the social environment for experimental or husbandry reasons, but the risk of deleterious consequences can be reduced by a good knowledge of the animals’ normal repertoire and careful monitoring of how the animals adjust to the new conditions. Attending to the social environment of captive primates is fundamental to their welfare.

The relationship between social behaviour and skin injuries (caused by horns) of loose housed horned cows was investigated on 35 dairy farms. While the frequencies of two agonistic behaviour elements (push and chase away) were positively correlated with the occurrence of skin injuries, the frequencies of butting and horning were not. Butting appears to have an ambivalent motivation, in that its occurrence is correlated positively both with agonistic behaviour and with social licking. Horning showed a positive correlation with social licking only. Four groups of husbandry conditions that may be associated with the occurrence of social behaviour and of injuries were distinguished: i) herd management, with variables including problem solving management by the farmer, integration of new cows, and dealing with periparturient and oestrus cows; ii) human-animal relationship, with variables including ability to identify individual cows, frequency of brushing the cows, number of milkers, and frequency of personnel changes; iii) animal characteristics, with the variable of herd size; and iv) stable characteristics, with the variable of space per cow (m2). The relevance of the husbandry variables investigated here had been confirmed in a previous stepwise regression analysis (Menke 1996). The variables for herd management and human-animal relationship conditions correlated in a consistent way with the occurrence of agonistic behaviour and/or of injuries, while most of them also correlated in the opposite direction with the occurrence of social licking. Herd size correlated positively with agonistic behaviour, but negatively with social licking. Space per cow correlated negatively with agonistic behaviour and injuries. In more than 70 per cent of the herds investigated, the levels of agonistic behaviour and of skin injuries were low, implying that horned dairy cows can be kept with less risk than is often assumed. We argue that such risks strongly depend on management factors that can be improved.

It has been claimed that the present farming environment does not meet foxes’ needs for social behaviour. In this study we measured the welfare of farmed blue foxes, Alopex lagopus, housed in two different social and spatial conditions: i) traditional housing (group T) where a male and a female cub were housed together and their vixen alone in standard (1.2m2) fox cages; and ii) family housing (group F) where a vixen and her five cubs were housed together in a connected six-cage system (7.2m2). Production-related welfare parameters (weight gain and the incidence of bite wounds on fur) as well as physiological ones (adrenal mass and serum Cortisol response to ACTH administration) were measured in these two groups.

No differences were found in any of the measured parameters between the vixens housed in traditional and family units. In cubs, there was less difference between the sexes in weight gain in group F than in group T, and a significantly lower weight gain was evident only in group T female cubs. The serum Cortisol level in response to an ACTH challenge was higher in group T cubs and independent of the sex of the animal, while heavier adrenals were observed in group T male cubs only. We conclude that the enlarged cage system combined with group housing had some beneficial effects on the measured performance- and welfare-related indicators in blue fox cubs.

The purpose of this study was to investigate the behavioural effects of keeping circus elephants in paddocks. Therefore some species-typical behavioural characters and the occurrence of stereotyped movements were observed and compared in unshackled paddock keeping versus shackled keeping. The investigation includes 29 elephants (19 Elephas maximus, 10 Loxodonta africana) at four circuses located in Germany and in Switzerland.

The results showed that paddocks offered more freedom for comfort, social and play behaviour since such activities were observed more frequently in paddocks than in shackled keeping. Also, stereotyped movements were nearly absent in paddocks and very frequent in shackled keeping. In comparison to shackled keeping, paddocks were more suitable for the needs of elephants.

Social role has been defined as a pattern of behaviour characteristic of a class of individuals within a group. The concept was developed by primatologists both to describe individual variation in behaviour in social groups and to be used in addition to hierarchy as a model for primate social organization. Cattle have been shown to express considerable individual variation in behaviour. Furthermore, cattle and primates show some similarities with respect to their social behaviour. This may indicate that the concept of social roles might be useful to those studying cattle behaviour. After a brief literature review it is concluded that the concept may indeed be applicable to cattle. The possible welfare implications of this are first, that it would offer a new approach for the study of individual differences in behaviour - important to the understanding of how animals cope with their environment in captivity. Second, it could help the understanding of social behaviour in domestic species. It is suggested that an interchange of ideas between primatologists and applied ethologists is needed.

In this paper social relationships (as defined by Hinde) between age/sex classes of kangaroos, wallabies and rat-kangaroos are reviewed and characterized by frequencies, direction and, where possible, intensity of behavioural interactions, by their patterning in sequences and by distance regulation. Male social organization in the wild for larger non-solitary species is organized in an age/size-related hierarchy. Frequent interactions among equal-sized males stabilize this hierarchy and large males by their simple presence deter younger ones from courting.

Depending on social organization in the wild, the presence of one or more males, sometimes males from different age classes, is desirable from the animal welfare standpoint.

The structure of breeding groups can be greatly improved in terms of welfare and breeding optimization, when a diversity of social relationships are as close to natural conditions as possible.

Ethological observations of the introduction of new charges into a large mixed-sex group in a dog shelter, and the later behaviour of the dogs in the run, were used to investigate a method of early assessment of the dogs’ reactions to the new situation. Subjects were divided qualitatively into four categories according to their interactional behaviour during the first two days (‘dog-oriented’, ‘human-oriented’, ‘dog & human friendly’, ‘asocial’). This classification was compared to an independent division resulting from statistical analysis of the dogs ‘ entry-sequences, and was found to be consistent for 80 per cent of dogs. One week after entry, both female and male dogs received distinctively fewer social interactions by conspecifics and tended to direct more interaction-initiating behaviour towards the keeper, thus demonstrating an integration process; females became more physically active and initiated significantly more interactions with other dogs; for males, the contrary was found. Qualitative comparison between first visitors and regular guests suggest that experienced dogs integrate faster, showing fewer behavioural signs of distress and engaging more often in investigatory behaviour. Results indicate that the assessment of dogs from their behaviour during the entry-sequence is a valid method to predict later tendencies. Males and females should be handled differently during introduction. The stress of entry into an existing group can therefore be reduced, improving the animals’ welfare.

When thwarted in a behaviour, laying hens show an increase in stereotyped pacing, displacement preening and a specific vocalisation known as the ‘gakel-call’. How these behaviours, which might serve as indicators of welfare, are influenced by social factors is not yet known. In this study, we investigated the effect of an audience (another bird or a human) on the expression of the gakel-call and other behaviours indicating frustration. Twenty-four Lohman Brown hens were trained to gain free access to food in a test cage. Sixteen hens were used as test birds and eight as non-test audience birds. The food-deprived test hens were tested for 15 min in a non-thwarting situation (food freely available) and for 15 min in a thwarting situation (food covered but visible). For both situations we investigated four different treatments: no audience in the adjacent cage; a non-thwarted audience bird in the adjacent cage; a thwarted audience bird in the adjacent cage; and finally a human audience. The durations of stereotyped pacing and displacement preening were significantly higher in test birds during thwarting than during non-thwarting; thwarted birds also gave significantly more gakel-calls compared to non-thwarted birds. The test birds, and also the audience birds, gave more gakel-calls when thwarted in the presence of a thwarted conspecific than when in the presence of a non-thwarted bird, but there were no significant differences in stereotyped pacing or displacement preening, which are usually associated with frustration. In conclusion, this study supports the view that the gakel-call signals frustration in laying hens. Furthermore, the state of the audience influences the occurrence of gakel-calls in thwarted hens. Thus, when using the gakel-call as a welfare-indicator, the social aspects of the vocal expression of frustration in laying hens should not be overlooked.

Timely adoption is essential for shelters to prevent unnecessary illness or euthanasia in cats (Felis catus). Many studies have examined the role of individual cat characteristics and environmental factors in facilitating cat adoptions, but none have looked at the role the number of cats being adopted plays. In this study, we examined whether or not adopting cats in pairs influences adoption times, in addition to commonly studied factors. We then collected video data on a small subset of cats to determine whether pairs that were adopted together differed behaviourally from pairs who were not. Our results demonstrate that cats who are adopted as part of a multi-cat outcome spent three days (42%) longer on the adoption floor than those adopted individually, independently of other factors such as age and coat colour. This difference increased to 13 days (185%) longer if the cat had a notification indicating they must be adopted together with another cat. While behavioural data show that these pairs of cats engage in significantly more affiliative behaviour with each other than cats who were adopted singly, there was a large discrepancy between which pairs the shelter classified as multi-outcome and those who would be classified that way based on behaviour alone. We suggest that decisions to place cats together should be made carefully given the potential adverse impacts of keeping cats in the shelter longer. Further, we suggest that guidance should be developed to help shelters accurately and consistently identify which cats merit a multi-outcome adoption.

Capybara (Hydrochoerus hydrochaeris) farming in Latin American countries was hampered at the outset by limited knowledge of species behaviour and inappropriate husbandry protocols, which resulted in low reproductive rates, lethal adult fights and consequent reduced well-being. As the peculiarities of capybara social behaviour are still ignored by many species’ breeders, both in commercial or research centres, we aim here to provide a review of successful experiences in Brazil by evaluating a number of social behaviour issues that are directly associated with the species’ welfare. We highlight special points on group composition and facilities needed, such as water tank and corral-trap structures, which may affect capybara health, productivity, and animal welfare. It has been shown that trying to form new aggregates by mixing adult or sub-adult animals obtained from different groups does not work. Conversely, we did not find a difference in the frequency with which mothers from the same group nurse their own young or those of other females. This knowledge may lead to successful trials for female adoption when necessary. In conclusion, capybara welfare is strongly linked to cohesion among animals. Additionally, assessment of vocal emissions is discussed as a potential, non-invasive measure to evaluate improvement in capybara handling procedures.

Herds of white-lipped peccary (Tayassu pecari) have historically been kept in captivity in order to replace stocks lost to hunting however the lack of knowledge regarding their species-typical behaviour remains an impediment to understanding their captive needs. Environmental enrichment has been suggested as an efficient way of decreasing aggression and apathy as well as increasing the expression of normal behavioural acts — such as play behaviour — which may, in turn, contribute to improved husbandry conditions. Therefore, the aims of this study were to describe play behaviour in this species and analyse the effects of environmental enrichment on such behaviour as well as on agonistic expression and inactivity. The occurrence of solitary and social play acts were recorded, as well as agonistic interactions and inactivity (resting positions) in two conditions (non-enriched and enriched with ball, hose and see-saw). This study included 24 captive peccaries three of which were juveniles, nine sub-adults and 12 adults, with a 1:1 sex ratio. The relationship between social dominance hierarchy and play behaviour was also analysed in each observational condition. Enrichment resulted in increased solitary and social acts of playing both in juvenile/sub-adult and adult peccaries. All the individuals played with the introduced objects and spent less time in resting positions throughout the enrichment phase. However, no decrease in agonistic interactions was observed and dominant individuals played more with the objects. Our study showed that environmental enrichment stimulated play behaviour in white-lipped peccaries as well as decreasing levels of inactivity; this may lead to improvements in the welfare of individuals in captive breeding centres.

Social interactions between individuals, such as co-operation and competition, are key factors in evolution by natural selection. As a consequence, evolutionary biologists have developed extensive theories to understand the consequences of social interactions for response to natural selection. Current genetic improvement programmes in animal husbandry, in contrast, largely ignore the implications of social interactions for the design of breeding programmes. Recently, we have developed theoretical and empirical tools to quantify the magnitude of heritable social effects, ie the heritable effects that animals have on their group mates’ traits, in livestock populations, and to utilise those effects in genetic improvement programmes. Results in commercial populations of pigs and laying hens indicate large heritable social effects, and the potential to substantially increase responses to selection in traits affected by social interactions. In pigs, including social effects into the breeding programme affected aggressive behaviour, both at mixing and in stable groups, indicating changes in the way dominance relationships are established and in aggressiveness. In laying hens, we applied selection between kin-groups to reduce mortality due to cannibalistic pecking. This resulted in a considerable difference in mortality between the low mortality line and the unselected control line in the first generation (20 vs 30%). Furthermore, changes in behavioural and neurobiological responses to stress were detected in the low mortality line, pointing to reduced fearfulness and stress sensitivity. These first results indicate that including social effects into breeding programmes is a promising way to reduce negative social interactions in farm animals, and possibly to also increase positive social interactions, by breeding animals with better social skills.

Captive breeding of peccaries is on the increase in neotropical countries. Few studies, however, have reported behavioural responses of wild animals under farmed conditions. Therefore, the aim of this study was to evaluate the effects of space allowance on the occurrence of social behaviour patterns on farmed collared peccary (Pecari tajacu). We observed three herds of collared peccaries each containing eight acquainted individuals. Using a 3 * 3 Latin square design, herds were allocated, in a random order, to one of the three experimental enclosures, each with a different size: 375, 750 and 1,500 m2 of total available area, each with three wooden shelters. We recorded all the occurrences of selected positive and agonistic behavioural patterns that occurred 90 min before and during feeding. Enclosure size had a significant effect on agonistic patterns of peccaries during feeding, in that more agonistic behaviour was observed in smaller spaces. We also found that shelter usage increased as space decreased. Differing space allowances, however, did not have an effect on the occurrence of positive interactions that were more frequent before compared to during feeding. We concluded that enclosure size had an effect on the expression of agonistic behaviours and the use of shelters by collared peccaries. Thus, animal welfare can be improved by adopting at least 187.5 m2 per peccary. In addition, our study also confirmed the importance of shelter areas in collared peccary husbandry.